Investigation of pharmaceuticals in aquatic environments on a national scale in France and french overseas departments
Résumé
A screening study of emerging contaminants was carried out in 2012 in surface waters in both metropolitan France and overseas departments (Martinique, Guadeloupe, Reunion, Mayotte and French Guiana) as part of the National Action Plan against pollution of the aquatic environment, which implies the regular update of the lists of substances to be included in monitoring programs. The study on 182 emerging compounds (100 molecules measured in surface waters, 134 in sediments and 191 in groundwater in overseas only) was performed at 200 sites (rivers and lakes in metropolitan France and overseas territories). Among the substances selected, more than 40 pharmaceuticals were analysed, with a total of 400 data collected for each substance for the surface waters (3 sampling campaigns) and 150 data for the sediments (1 sampling campaign). Overall, out of the 22 pharmaceuticals monitored in surface water, 16 were analysed above the LOQ at least once in rivers during the three sampling campaigns in metropolitan France. Highest concentrations were measured for anxiolytics (oxazepam, lorazepam and diazepam). For the sediment matrix, out of the 28 measured pharmaceuticals, 15 were quantified in rivers or in lakes in metropolitan France. The highest concentrations were measured for amiodarone, diosgenin and econazole (Max. Conc. 18 ng/g). It was the first time that Water Agencies acquired data on these compounds in sediments. For many compounds such as carbamazepine (frequency of quantification of 71.0%), oxazepam (60.3%) or ofloxacin (23.7%), it was the first time that they were measured at large spatial scale (115 sites) and with such a number of samples (n=400) in France. For some pharmaceuticals, the improvement of analytical methods (order of LOQ of ng/L, significantly lower as compared to previous studies carried out by water agencies) helped to have a better frequency of quantification. As an example, the frequency of quantification of ketoprofen increased up to 51.5% (instead of 9.3%) and sulfamethoxazole up to 38.0% (instead of 1.4%). Almost all substances were quantified at reference sites in the water matrix, but for sulfamethoxazole, ketoprofen and oxazepam concentrations were near the LoQ values. For sediments, urban and agricultural sites were overall more contaminated as compared to reference sites. Diosgenin was highly measured in agricultural and reference sites but not in urban sites. Nicotinamide was observed in both agricultural and urban sites but never quantified in reference sites. In overseas territories, a short list of pharmaceuticals was monitored in both groundwater and surface water to identify a possible link between the two water categories. These combined studies allowed to identify which water bodies is more contaminated (ex. ketoprofen, even if always detected in both water categories, is more an issue for surface water as compared to groundwater). In marine compartments, two pharmaceuticals were quantified at high concentrations in POCIS (carbamazepine and ketoprofen) in a large number of sites in Metropolitin France. Miconazole, amiodarone and diosgenin displayed a frequency of quantification of about 30% in sediments. In conclusion, this screening study allowed the collection of about 15000 records for pharmaceuticals in French aquatic environments. Further to this screening campaign, 11 pharmaceuticals substances (8 for water and 3 for sediment) have been included in the national Watch List for future monitoring in the French surface aquatic environment (2016–2021) (as a result of a prioritisation exercise based on frequency of quantification, frequency and degree of PNEC exceedance and hazardous properties). This study also contributed to increase the knowledge about emerging pharmaceuticals in French marine waters.